Cokin Special Effects Filters

What are the main advantages of the COKIN CREATIVE FILTER SYSTEM compared to screw-in filters ?

Easy to use: Simply screw the adaptor ring onto your lens, snap the holder and slide the filter(s) !Economical: If you have several lenses with different filter threads or sizes, you need only one set of square filters. With screw-in filters, you need one set of filters for each filter thread or size. It may thus be very costly.Dedicated: The COKIN System will allow you to position the effect at your own will. Combination of filters is particularly easy and convenient. Both are impossible with screw-in filters. It is therefore a real tool.